From 96d8569563916fe2f8fe17317e20e43f54f9ba4b Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Thu, 24 Oct 2024 10:21:30 +0200 Subject: [PATCH] media: vivid: fix buffer overwrite when using > 32 buffers The maximum number of buffers that can be requested was increased to 64 for the video capture queue. But video capture used a must_blank array that was still sized for 32 (VIDEO_MAX_FRAME). This caused an out-of-bounds write when using buffer indices >= 32. Create a new define MAX_VID_CAP_BUFFERS that is used to access the must_blank array and set max_num_buffers for the video capture queue. This solves a crash reported by: https://bugzilla.kernel.org/show_bug.cgi?id=219258 Signed-off-by: Hans Verkuil Fixes: cea70ed416b4 ("media: test-drivers: vivid: Increase max supported buffers for capture queues") Cc: stable@vger.kernel.org --- drivers/media/test-drivers/vivid/vivid-core.c | 2 +- drivers/media/test-drivers/vivid/vivid-core.h | 4 +++- drivers/media/test-drivers/vivid/vivid-ctrls.c | 2 +- drivers/media/test-drivers/vivid/vivid-vid-cap.c | 2 +- 4 files changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/media/test-drivers/vivid/vivid-core.c b/drivers/media/test-drivers/vivid/vivid-core.c index 00e0d08af357..4f330f4fc6be 100644 --- a/drivers/media/test-drivers/vivid/vivid-core.c +++ b/drivers/media/test-drivers/vivid/vivid-core.c @@ -910,7 +910,7 @@ static int vivid_create_queue(struct vivid_dev *dev, * videobuf2-core.c to MAX_BUFFER_INDEX. */ if (buf_type == V4L2_BUF_TYPE_VIDEO_CAPTURE) - q->max_num_buffers = 64; + q->max_num_buffers = MAX_VID_CAP_BUFFERS; if (buf_type == V4L2_BUF_TYPE_SDR_CAPTURE) q->max_num_buffers = 1024; if (buf_type == V4L2_BUF_TYPE_VBI_CAPTURE) diff --git a/drivers/media/test-drivers/vivid/vivid-core.h b/drivers/media/test-drivers/vivid/vivid-core.h index cc18a3bc6dc0..d2d52763b119 100644 --- a/drivers/media/test-drivers/vivid/vivid-core.h +++ b/drivers/media/test-drivers/vivid/vivid-core.h @@ -26,6 +26,8 @@ #define MAX_INPUTS 16 /* The maximum number of outputs */ #define MAX_OUTPUTS 16 +/* The maximum number of video capture buffers */ +#define MAX_VID_CAP_BUFFERS 64 /* The maximum up or down scaling factor is 4 */ #define MAX_ZOOM 4 /* The maximum image width/height are set to 4K DMT */ @@ -481,7 +483,7 @@ struct vivid_dev { /* video capture */ struct tpg_data tpg; unsigned ms_vid_cap; - bool must_blank[VIDEO_MAX_FRAME]; + bool must_blank[MAX_VID_CAP_BUFFERS]; const struct vivid_fmt *fmt_cap; struct v4l2_fract timeperframe_vid_cap; diff --git a/drivers/media/test-drivers/vivid/vivid-ctrls.c b/drivers/media/test-drivers/vivid/vivid-ctrls.c index 8bb38bc7b8cc..2b5c8fbcd0a2 100644 --- a/drivers/media/test-drivers/vivid/vivid-ctrls.c +++ b/drivers/media/test-drivers/vivid/vivid-ctrls.c @@ -553,7 +553,7 @@ static int vivid_vid_cap_s_ctrl(struct v4l2_ctrl *ctrl) break; case VIVID_CID_PERCENTAGE_FILL: tpg_s_perc_fill(&dev->tpg, ctrl->val); - for (i = 0; i < VIDEO_MAX_FRAME; i++) + for (i = 0; i < MAX_VID_CAP_BUFFERS; i++) dev->must_blank[i] = ctrl->val < 100; break; case VIVID_CID_INSERT_SAV: diff --git a/drivers/media/test-drivers/vivid/vivid-vid-cap.c b/drivers/media/test-drivers/vivid/vivid-vid-cap.c index 69620e0a35a0..6a790ac8cbe6 100644 --- a/drivers/media/test-drivers/vivid/vivid-vid-cap.c +++ b/drivers/media/test-drivers/vivid/vivid-vid-cap.c @@ -213,7 +213,7 @@ static int vid_cap_start_streaming(struct vb2_queue *vq, unsigned count) dev->vid_cap_seq_count = 0; dprintk(dev, 1, "%s\n", __func__); - for (i = 0; i < VIDEO_MAX_FRAME; i++) + for (i = 0; i < MAX_VID_CAP_BUFFERS; i++) dev->must_blank[i] = tpg_g_perc_fill(&dev->tpg) < 100; if (dev->start_streaming_error) { dev->start_streaming_error = false;